>>50277350It's a decent fake, but there's some clear reasons why this is fake. Biggest issue is the sword feather. It doesn't feel natural, it feels too lacking in detail, and it doesn't even feel practical to use. Compare it to how Dartrix and Decidueye hide their feather projectiles under their wings. This design also doesn't really have ANYTHING special going for it beyond the aforementioned swords. It's a solid design on its own, but it's just too boring for what usually gets by Game Freak. There's just not a lot of inspiration behind this one.
As another matter, where is its flaw? As Ken Sugimori himself said, there's always at least one deliberate "flaw" included in a Pokémon design to make it feel more believable. Faecoco's could easily be its hair or its goofy tail, for example. What exactly could be considered a flaw here? Its chest feathers? This design just seems TOO perfect, and thus less believable. Lastly, having art of it threatening Ash and Pikachu actually make it to print seems really out of character, even for behind-the-scenes drawings.
There's other oddities like it losing the distinct blue feet from Quaxly entirely, and I didn't even get into any possible issues with the page itself. Point is that there's some damn clear signs this is fake. That said, I'll give it some credit at least. It is at least a pretty cool design, and I kind of adore the art of it swimming with Quaxly.